Wireless communication systems have been widely deployed to provide various types of communication services such as voice service or data service. In general, a wireless communication system is a multiple access system that supports communication with multiple users by sharing available system resources (e.g. a bandwidth, transmission power, etc.) among the multiple users. The multiple access system may adopt a multiple access scheme such as Code Division Multiple Access (CDMA), Frequency Division Multiple Access (FDMA), Time Division Multiple Access (TDMA), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier Frequency Division Multiple Access (SC-FDMA), or Multi Carrier Frequency Division Multiple Access (MC-FDMA).